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The most common email I get from people who have visited this blog is inquiries about the dark color of the background in the screenshots. No it’s not a custom UI, I just have a custom menu with a bunch of stuff including two ridiculously simple scripts… one which cycles the background color in all viewports and one which sets them to this dark grey.

I chose this color for a couple of reasons.

With a darker color, particles are much more visible, meaning I can display them as single pixels.

The color is dark but just light enough to easily see black wireframes.

Have you ever opened Softimage in a dark room full of people using Maya and Nuke? It’s like switching on a searchlight. The light grey color scheme of the Softimage UI is waaaay to bright.

These two little scripts go a long way towards my personal enjoyment of the software. I won’t bother to display them in the post (wordpress kills the formatting), but here’s a file for each…

Since we’re on the topic… Softimage needs a new UI. It’s elegant and functional in many ways, but dated. The light grey is glaring, the huge arrow button looks absurd to new artists, (they’re right) and I have a strong suspicion that it’s a major factor which keeps new artists from Softimage. Just my $0.02.

Unlike most of the examples, I built this specifically to show how a deformer can be constructed with simple visual guides. So the good news is that it’s all nicely commented. This example shows the structure of a deformation, some tricks for making viewport guides, and the taper function itself (originally published by Alan Barr, it’s quite simple).

The down side is that I didn’t want to get into matrix transforms for the example, so this implementation is only on the object’s local Y axis. This limits it’s production value (not that there’s a great need for another taper deformer.) It’s an example, not a tool – adding in the transforms to make the taper axis arbitrary isn’t too difficult, but as I was making this I realized it was going to make the entire thing unreadable and that I was out of time – I have paying work I need to get to. ^_^ So here it is, as-is. Cheers – AM

Update

Had a little time and I hated leaving this in a state that wasn’t that useful, so I added in the additional kinds of control I usually have in production compounds (in this case, mainly the optional ability to deform on an arbitrary axis as supplied by a control object like a null, and minor cosmetics.)

A taper deformer isn’t high-tech feeling and exciting, but it’s useful in everyday practice, and more to the point this is a structure that can be used for many useful kinds of deformations. For instance, once I had the taper structure it was pretty simple to replace the internal “taper” formula with one to do a twist:

I’ll share out the twist version eventually, in the meantime here’s the full taper compound (if you look inside you’ll see what I was getting at by the arbitrary axis adding a lot of seeming complexity, but it’s really not complex, ICE just tends to look that way when there are a lot of different things all connected.)

Been playing with Vray. I like it. This is an “out of box” render of some strands, no effort on my part to properly light it, which really is a requirement for fine strands/hair etc. Still, not bad, they have a nice hair shader. I’m less interested in character hair than in fine detail fibers as VFX elements, so I’ll have to see what other looks I can coax out.

This amount of strands doesn’t even come close to taxing Softimage, it’s still interactive on my box…but rendering it at 2k took about 20 minutes, without any optimization. I’d guess that with some effort adjusting some settings I could get a better look at about 2x the speed, which isn’t bad, considering this is a GI render.

It’s a bit splotchy and the exposure is meh – chalk that up to me being a Vray noob. Looks like I was a bit too aggressive with the jpeg compression, too… The full render is much cleaner, and of course this is just a beauty pass, no passes or color correction. A decent lighter no doubt could take this to another level. Hey, I’m a VFX guy I hardly ever get to render stuff.

I’d like to get a feel for how much impact more strands will have on render time. I may have to try a “stress test” over the weekend to see what the reasonable limit for a single machine is in terms of numbers of strands I can get into a 2k half float render while still maintaining this look as a minimum quality…

There is an awesome thread on the softimage list where the small pipeline enhancements softimage users tend to accumulate in their personal collections are being discussed. In it I vowed to share mine to the community as a whole over time on this blog. So here’s the first one… a little python script I keep in a custom menu, which writes a log (as an anotation in the explorer) of distances between objects.

I considered sharing my personal workgroup in it’s entirety, but there’s a lot of trash in there I wouldn’t want to burden people with, plus a considerable amount of stuff which Isn’t mine to share. So until I make a “clean” workgroup I’ll just have to post bits and pieces…

I am a big fan of Polynoid. Ever since their first images of cybernetic snails came out I’ve been hooked on their often-dark blend of art-meets-tech imagery. http://www.vimeo.com/21849607

Fabian Pross of Polynoid was, for a while, maintaining a very cool blog (come on Fabian, post new stuff!) One post in particular puts into words a critical concept I and many others often try to get across to newer artists – the importance of avoiding simulation where possible.

Simulations usually don’t quite achieve what you want them to, visually. The trap people fall into is to try to force a behavior out of a simulation. You end up making endless iterations while the setup you’re using grows more and more bloated and slow. A single directoral change becomes a nightmare. You lose control and the limitations of your setup starts to dictate the look.

The solution is to create what I think of as “deterministic” solutions – setups which change over time, but in very strict ways you specify. That’s one of the things I was trying to get at with the “post simulation” tutorials, the benefit of offloading much of the look outside of what is simulated.

Even skilled vfx artists fall into this trap with some regularity. I can’t say how many times I’ve seen production scenes which have grown bloated to the point of containing hundreds of forces and collision objects just to try to achieve a simple effect. You can’t afford it. A simple directoral change blows the whole thing apart. Stop. Take a deep breath. Don’t go over that cliff. Simulate judiciously, in small doses, only where you have to.

Simple simulation + deterministic stuff for a complex look = control.

And control is what makes a VFX artist, in my mind. Anyone can pull levers until they get a nice result out of fumeFX. But to achieve brilliant results which are new or spot-on to what is needed in prodution, you have to have control – be it in fumeFX, ICE, Realflow, Houdini or whatever. And one of the best ways to achieve control is to only simulate where you have to, and keep it simple when you do.

Fabian puts this idea into words better in this post. Even if the techniques he uses here are specific to ICE, the underlying message and workflow is the same everywhere – avoid simulation to gain control and speed.

Sparta

Even when you use simulation, who says that you have to stop there? Bake it and use it as an element you shape further or build on. This concept is really powerful. A good example of this idea in practice is demonstrated by a little DCC-agnostic tool called Sparta. Simulate, then shape the results.

In the “postSim” tutorial we made shapes out of strands by constructing arrays of point positions. Many ICE users, myself included, forget that there are a bunch of shapes provided already which can be used in this fashion. They are in the “Debugging” section, because arrays like these can also be used with ICE attribute display properties to create onscreen widgets (hint: …or to add points to a pointCloud…)

I’ve found the factory nodes to be quite handy for a number of things, but I wanted some other shapes of my own (such as a star and spiral) – so I made them, as well as made some adjustments to what was already available (with some digging) to suit my personal preferences. Here is a scene with a number of them, each packaged as a compound.

While experimenting around with these elements as display objects, I made a “protractor” compound.

It’s of limited production use because of a current problem with how softimage displays these elements in a shaded or hidden line view, and because it wasn’t particularly designed as a tool… it just evolved while I messed around. But it serves as an example of how you can use the “Debug” nodes to create visual feedback (another good example of these debug elements is the factory “bend” deformer in ICE.)

Judicious use of these display attributes can make a packaged compound much more useful, as well as act as a handy jumping off point to make interesting shapes with strands etc. Enjoy! – AM

SI-Community has a “resource dump” for scraps of stuff people want to share in an unfinished or flawed state for others to pick over. This “Greeble push deformer” I made a while back is IMHO a good candidate for such a bin, so I’m sharing it there.

BTW, if you don’t regularly visit SI-Community, why not? It, rray.de and the softimage mailing list are the heart of the softimage community. And vimeo:

It works fine, so why am I putting it in a “public rubbish bin” rather than releasing it with fanfare? Well, I’m not particularly proud of it lol. Here are some reasons why this isn’t awesome:

It’s a “push” style deformer, meaning it doesn’t create geometry it just deforms it. That kinda blows, it means you have to start with a very dense mesh. In fact, this is the main reason why I haven’t released the loads of terrain stuff I’ve got hanging around – I haven’t come up with a good way to make the geometry as I go and add detail only where it’s needed that isn’t too slow.

This is just worley noise hooked to a push deform structure and a repeat node. I was sure a zillion people were going to do it, in fact I’m amazed I haven’t seen this compound done better from someone else. Surely we have some Star Wars fans somewhere messing with ice?

I never bothered to add in a control to decrease the amplitude of the noise per generation. This would be easy enough to sort out but I never got around to it.

The deformer respects normals, but the noise itself is spatial, in other words it doesn’t “flow” along the surface, which would be nice. Note the sphere shape in the video, instead of looking like the death star it reveals this spatial, circular character of the worley noise.

But it’s hardly doing any good sitting on my hard drive so here you go – consider it an example of how to iterate a push deformer. Try turbulence instead of worley noise and it will look a little terrain like. Change the worley noise and you can make some crater-like looks. So it sucks, but in a kinda fun way. Hope it’s of use to someone.

To make a point that the underlying concepts introduced in this simple tutorial are far more important than the simple look of our example, here are some images which derive from the simple parametric circle equation discussed. The scene used to make the anaglyph is below. This isn’t rocket science stuff, this is novice level ICE… and much of it applies to realflow, thinking particles, maya or whatever. Cheers – AM

So, we’ve made a strand circle which rings our original point positions from the simulation, now let’s make those circles align with the rotation of the simulated particle. In practice this is very, very simple. Just insert a “rotate vector” node after you calculate the coordinates on a circle for the strand points, and then use the particle orientation as the input rotation.

Ok, that was nice, but why did it work?

Point positions are vectors. Vectors are displacements:

This is one of the simple but critical concepts that is the real purpose for me writing this series of posts, because it’s a foundational way of thinking which lets you come up with solutions to problems every day.

What is a point? It’s a place, within a space. A particle can have all kinds of attributes, like color size and orientation. But a point is just a position, it only has a single value, a vector (x,y,z). In a manner of thinking, a point is a vector. The vector which describes a point is a direction and distance from the origin. It’s a displacement from that point of reference. When you talk about “global” and “local” space you are talking about different frames of reference, different points of origin from which to draw a vector describing points.

So, what we really did when we calculated an array of strand positions on a circle was make an array of vectors. Hence, rotating those vectors is really the same thing as rotating the strand point positions to match the orientation of our original particle. Points are vectors, they are offsets (or displacements) from an origin. And ICE is very, very good at doing stuff with points vectors. You can call these manipulations vector math if you want, but that in itself doesn’t make it beyond your average artist, who like ICE are also very, very good at manipulating points. If you are an artist you already have an intuitive grasp of vectors! You just need to define some terms, so that saying stuff like “rotate a vector” translates to the visual adjustments you do in your head day in and day out.

Seeing stars… and why modulo is so handy:

Ok, cool. We have a bunch of strand rings centered and oriented where our simulated particles were. Let’s make the rings star shapes, as a way of talking about another useful technique in ICE (it’s useful all over in fact), making patterns via the modulo function.

Ok, a digression first – some housekeeping. By now you’ve realized this isn’t one of those step-by-step makes-a-scene tutorial, I’m discussing more and glossing over a lot of the details you may need to actually plug all this together. I really should have provided a sample scene earlier, I don’t want you focusing on plugging nodes together, the whole point of this is the underlying ideas. So here you go. A sample scene with nifty comments and stuff. If all you want is a scene that will make circles and stars, there you go. And it was made with an educational license, even. But if you want the ideas used so you can make all kinds of other stuff, well then dear reader, read on.

The modulo function is just an instruction to divide two numbers and pick out the decimal remainder of that division. If you feed a linear sequence of numbers (like the index of an array: 0,1,2,3… call any of these numbers “n”) into the modulo function, you get a value counting up between 0 and 1. You can use this to identify every “n’th” item in your list. In fact if you crack open ICE’s “every n’th particle compound etc you will basically see exactly this.) If you can do things every “n’th” time, you can make patterns. Think about it. Braiding hair, knitting, drawing a dotted line – making almost any pattern involves counting and every “n’th” count doing something differently. Modulo is how you do that kind of thing in ICE (and elsewhere. Hey, realflow has an ICE like system now. And it works in scripting too. This math stuff pops up everywhere. The big secret is this – it’s just a way of looking at things you probably already do really well.

I’m a visual thinker so when I was first learning about modulo I had to scribble on a napkin, with results something like this:

All a star shape is, is a pattern where we take every other point on our circle and change it’s radius. Now we know how to find every other point from our list (the array) of strand positions, so we just change the radius of the formula we used to make the circle for those points. And you get a star.

Cooooool.

Ok, so just one last part to this tutorial, and a brief one – how to take the single circles we made and, using the earth-shaking power of ICE and the post-simulation region, turn that result into a lot of circles: all different and making little atom things like we see in the example video. And in fact, the example scene here already shows you how, so we’re not even going to do much besides discuss it and crack bad jokes. Cheers. – AM